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107 lines
5.3 KiB
HTML
107 lines
5.3 KiB
HTML
4 years ago
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html>
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<!-- Copyright (C) 1988-2018 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3 or
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any later version published by the Free Software Foundation; with the
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Invariant Sections being "Funding Free Software", the Front-Cover
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Texts being (a) (see below), and with the Back-Cover Texts being (b)
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(see below). A copy of the license is included in the section entitled
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"GNU Free Documentation License".
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(a) The FSF's Front-Cover Text is:
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A GNU Manual
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(b) The FSF's Back-Cover Text is:
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You have freedom to copy and modify this GNU Manual, like GNU
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software. Copies published by the Free Software Foundation raise
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funds for GNU development. -->
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<!-- Created by GNU Texinfo 6.4, http://www.gnu.org/software/texinfo/ -->
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<head>
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<title>Registers (GNU Compiler Collection (GCC) Internals)</title>
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<meta name="description" content="Registers (GNU Compiler Collection (GCC) Internals)">
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<meta name="keywords" content="Registers (GNU Compiler Collection (GCC) Internals)">
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<meta name="resource-type" content="document">
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<meta name="distribution" content="global">
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<meta name="Generator" content="makeinfo">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<link href="index.html#Top" rel="start" title="Top">
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<link href="Option-Index.html#Option-Index" rel="index" title="Option Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="Target-Macros.html#Target-Macros" rel="up" title="Target Macros">
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<link href="Register-Basics.html#Register-Basics" rel="next" title="Register Basics">
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<link href="Type-Layout.html#Type-Layout" rel="prev" title="Type Layout">
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<style type="text/css">
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-->
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</style>
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</head>
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<body lang="en">
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<a name="Registers"></a>
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<div class="header">
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<p>
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Next: <a href="Register-Classes.html#Register-Classes" accesskey="n" rel="next">Register Classes</a>, Previous: <a href="Type-Layout.html#Type-Layout" accesskey="p" rel="prev">Type Layout</a>, Up: <a href="Target-Macros.html#Target-Macros" accesskey="u" rel="up">Target Macros</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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</div>
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<hr>
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<a name="Register-Usage"></a>
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<h3 class="section">18.7 Register Usage</h3>
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<a name="index-register-usage"></a>
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<p>This section explains how to describe what registers the target machine
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has, and how (in general) they can be used.
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</p>
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<p>The description of which registers a specific instruction can use is
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done with register classes; see <a href="Register-Classes.html#Register-Classes">Register Classes</a>. For information
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on using registers to access a stack frame, see <a href="Frame-Registers.html#Frame-Registers">Frame Registers</a>.
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For passing values in registers, see <a href="Register-Arguments.html#Register-Arguments">Register Arguments</a>.
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For returning values in registers, see <a href="Scalar-Return.html#Scalar-Return">Scalar Return</a>.
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</p>
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<table class="menu" border="0" cellspacing="0">
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<tr><td align="left" valign="top">• <a href="Register-Basics.html#Register-Basics" accesskey="1">Register Basics</a>:</td><td> </td><td align="left" valign="top">Number and kinds of registers.
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</td></tr>
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<tr><td align="left" valign="top">• <a href="Allocation-Order.html#Allocation-Order" accesskey="2">Allocation Order</a>:</td><td> </td><td align="left" valign="top">Order in which registers are allocated.
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</td></tr>
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<tr><td align="left" valign="top">• <a href="Values-in-Registers.html#Values-in-Registers" accesskey="3">Values in Registers</a>:</td><td> </td><td align="left" valign="top">What kinds of values each reg can hold.
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</td></tr>
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<tr><td align="left" valign="top">• <a href="Leaf-Functions.html#Leaf-Functions" accesskey="4">Leaf Functions</a>:</td><td> </td><td align="left" valign="top">Renumbering registers for leaf functions.
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</td></tr>
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<tr><td align="left" valign="top">• <a href="Stack-Registers.html#Stack-Registers" accesskey="5">Stack Registers</a>:</td><td> </td><td align="left" valign="top">Handling a register stack such as 80387.
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</td></tr>
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</table>
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</body>
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</html>
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